Download Making war on waste

Making war
on waste
The world
population
increase
is
posing zn unparalleled
food dilemma for
the 2 1st century. Yet every year millions
of tons of fish that could provide protein
for people, is being ground up fo feed
livestock in the industrialized
countries,
or, worse sfill, 6 simply thrown away. In
the following
article
W.H.
Allsopp,
Associate
Dir&or,
Fisheries,
with the
Centre’s Agriculture,
Food and Nutrition
Sciences
Division,
explains
how and
why such waste occurs, examines home
of the moral and political
issues involved,
and presents
some practical
5OldO”5.
ml recently the conventional
wiscountries
U” dom !n many developing
has been that the quickest and easiest
way to develop
a fishing industry
is
through fish meal production
and other
expo~ products like shrimp, lobster and
tuna. Inflation,
the portents of the ongoing Law of the Sea Conference,
and
improvements
in processing technology,
however,
have combined
to bring a
gradual
change
in policy
that emphasizes the need for domestic
selfsufficiency
in food, and recognizes
the
value of fish products as an important
source of protein.
One example of wasted fish resources
is the shrimp trawling
by-catch of fish.
Wherever
the outflow
of large tropical
rivers enriches
the bottom
feed organisms on a broad continental
shelf
outspread,
the occurrence
of large
shrimp - sometimes called prawns has given rise t6 shrimp trawling
enterprises. For over 30 years such shrimp
fisheries
have been exploited
by the
“Gulf of Mexico”
type of shrimp traw-
lers, which are mainly owned by American and Japanese companies.
However,
large quantities
of fish are caught incidentally
in the trawling
operation,
and
this “by-catch”
is usually discarded
at
sea, or in a few cases is converted
to
animal feed.
International
shrimp trawling
companies now fish in the Gulf of Mexico,
and off the coasts of South America, East
and West Africa,
India and Southeast
Asia. It has been estimated that the fish
by-catch may total an annual average of
at least 5 million tons of fish jettisoned in
the tropical
seas of the world, while 1
million
tons of shrimp
are landed
worldwide.
Shrimp, not fish
Because it is difficult
io accept that
such fantastic waste occurs, the complexity of the problem should be clearly
explained. The vessels are designed with
a refrigerated
hold capacity of 15 to 30
tonsofshrimp.They
haveacrewofthree
to five, are highly powered
(450 hp
engines)
and costly to operate.
The
capital cost of such vessels varies from
US $150,000 to $250,000 with operating costs and crew payments depending
on catch,efficiencyand
location.Shrimp
trawlers operating off Guyana, for example, generally
gross annual
earnings
equivalent
to the initial investment
on
the vessel. This can be done (with
resulting
profits to owners
and crew)
only if the hold is filled with shrimp, not
fish! Various factors such as temperature
of the hold, crew size and time at sea,
are designed
exclusively
for handling
shrimp.
Further, the great bulk and variation of
the fish that are caught make it impracti-
cal to accommodate
the total by-catch
with the present system. The value of this
fish (about 10 cents/lb)
compares
adversely with the price of shrimp (at least
Blilb).
The fish is therefore
thrown
overboard
in its stunned condition.
It is
eaten then by sharks, gulls and scavengers.
The problem
is not only economic,
but also technological.
In the tropical
seas as many as 50 fish species may be
caught in a trawl. They vary in size,
chemical
content
(white or oily) and
some may even be poisonous.
The
quantity of fish caught will vary with the
place (bottom type, depth and currents),
time of day (fish are generally
more
active in daylight than shrimp) and time
of year (the rainy season causes outflows
from distant estuaries that affects the
availability
of fish). As some species of
fish become
mature and gravid,
the
chemical
composition
of the flesh and
even its palatability
varies. Generally the
weight of shrimp caught is between 10
and 30 percent of the total catch landed.
This mixed bag of fish would be difficult
to process without some sorting between
oily and white fish types. However,
the
fishing operation
is generally
done at
night, the crew is too small and there is
too little time between the landing of the
twin trawls.
From the Doint of view of oDerational
efficiency
only major quantities
of acceptable market fish can be considered
for collection
aboard or easy processing
ashore. Assessments along the Guyana
shelf estimated that about 200,000 tons
of edible fish, consisting of eight major
white flesh types, could be obtained
annually
from the fleet of between 175
and 210 trawlers. Yet the countries ofthe
3
oMth;coastof
Scientists ashore experiment with new
processing techniques.
&yana.
Caribbean
import
the equivalent
150,000tonsoffreshfishannually!
of
Unacceptable
w&e
Such a waste of consumable
fish is
unacceptable,
and solutions for its satisfactory use are being sought throughout
the tropical world. These approaches are
considering
ways of handling the fish at
sea, systems for collecting
and transportation from shrimp trawlers,
and the
processing of a mixed bag of species.
The
development
of shrimp-fish
separator
trawls
has shown
promise.
Alternatives
include the use of detached
floating cod-ends (nets), and refrigerated
sea water (nsw) tanks on the decks of
trawlers in which the day’s catch can be
held. Both systems require the retrieval
of the catch by a collection
vessel
operating along with the shrimp trawling
fleet. The vessels with RSW systems used
by the Pacific herring fleet off British
Columbia
are considered
sufficiently
adaptable
for the exercise.
However,
until the bulk handling of the by-catch is
proven practical and efficient,
industrial
scale processing
ashore will
not be
readily applicable,
since the landed cost
of the fish will be too high, even before
processing,
for low-income
consumers,
who are the target population.
To test the practicality
of using this
fish, the Cuyanese government
required
each shrimp trawler coming to the Port
of Georgetown
to land its last few days
by-catch. This totalled about 2,400 tons
a year, however the sudden volume of
fish brought
into the market created
problems in handling,
processing,
cold
storage,
sales and distribution.
In a
tropical country so large a volume of fish
is not easy to handle unless an efficient
industrial
infra-structure
already exists.
The resultant fish spoilage
and waste
leads to a spirit of frustrating
discouragement both for the shore handlers and
for the fishermen.
4
Since early 1973 the IDRC has been
supporting
the Guyanese
government’s
efforts to solve these problems.
Experiments in processing the mixed bag of fish
using deboning machines have provided
an extruded
flesh quite free of bones,
scales and skin. The waste (comprising
fish bones and skin) can be converted to
fish meal, while the cornminuted
fish
flesh is now a new raw-material.
Tests
have been conducted
in the project to
make dried, spiced or salted products
which are stable at normal temperatures,
and can be packaged in sealed plastic
bags and sold at low cost.
Additionally
the project plans to make
products of higher market value. That
portion of the catch that comprises fish
of higher consumer
demand
is to be
processed as fillets or specialty products.
These are intended to contribute
appreciably to defraying the processing costs,
thus permitting
the bulk preparation
of
lower-cost
stable fish products that are
within the reach of rural communities
where refrigerated
storage is not widely
available.
Similar
approaches
At an IDRc-sponsored
workshop
in
Thailand in 1974 similar situations were
described
in Southeast
Asia. Parallel
approaches
are being made through fish
technology
laboratories
in India, Thailand and Indonesia to solve the problem
of the waste of the by-catch.
It was
pointed out that without any increase in
fishing effort, more than 1 million tons
could be available
from the by-catch of
shrimp trawling in that region.
The often published
figures of fish
production
and the gap in protein
requirements
of the tropical
belt of the
developing
world emphasize the obligation to utilize such incidental
catches of
fish-not
for fish meal to feed livestock
or pets, but for direct human consumption.
While the world’s fish production
has
increased from 33.3 million tons in 1958
to 66 million tons in 1973, doubling
in
15 years, there has been a decline
in
direct
consumption
of fish from 84
percent
of the landed
catch to 60
percent,
with
a comparative
rise in
industrial
processing (for fish meal etc.)
from 16 percent to 40 percent.
This means that the current trend is to
convert to fish meal, almost the equivalent quantity of fish (26.2 million tons) as
was directly consumed by man 15 years
ago (28 million
tons). The agonizing
corollary
of this is that the increased
catch converted into fish meal has come
largely
from the oceans
adjacent
to
protein-deficient
developing
countries,
and sold to feed the livestock
of the
affluent nations of the world - in North
America, Europe and Asia.
There is concern among the traditionally powerful
high-seas fishing nations
that the Law of the Sea Conference
will
limit their fish production.
The grave
concern
of the developing
countries,
however,
is that mechanized
fishing off
their shores removes large quantities of
fish, much of which is wasted, while the
remainder goes to countries where there
is no food or protein
shortage.
Such
fishing benefits neither the people nor
the economy
of the coastal states, and
with
the ever-increasing
costs
of
technology,
manufactured
goods, ser.
vices and fuel, there is little hope that
they can compete with the established
fishing nations.
With the new focus on self-sufficiency
in food in the developing
world, a more
humane perspective
is required by the
advanced
technologies
of the industrialized
world.
Such a perspective
should
lead to concerted
efforts
to
prevent such unacceptable
“waste”
of
the valuable
by-catch
from tropical
shrimp trawling as a valuable source of
food for man.
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